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Archive | August 2016

Due to the the ever-expanding data center consolidation, virtualization and cloud technologies, network installers feel the urge to maintain a competitive advantage of their infrastructure. Except for the performance, bandwidth and latency in datacenter cabling, management and operational agility and simplicity have also elevated themselves to the top mind of data center architects and operator. Cisco Nexus 900 series represents a familiar starting point on the journey toward a new era in software-defined network, which is announced to be the most port dense and power efficient plus fastest packet forwarder and programmable data center modular switch in the industry. This article introduces basic information of Cisco Nexus 9000 series and the cabling solutions for Nexus 9508 switch.

Cisco Nexus 9000 Series Switch

According to Cisco’s announcement, the Nexus 9000 Series switch is the foundation of the Cisco next generation data center solution. The Cisco Nexus 9000 Series switch contains two main branches including the Nexus 9300 series fixed switches and Nexus 9500 series modular switches. Of particular interest is the Nexus 9508 of 9500 series, which is impressive in terms of performance, power efficiency, 10/40GbE and future 100GbE port density, programming environment and orchestration attributes. The following image shows the inner structure of the Cisco Nexus 9508 switch.

Cisco Nexus 9508 can offer up to 8 line cards slots with a comprehensive selection of modular line cards in a 13RU space. There are totally three line card options available: 48 port 1/10GbE SFP+ with four 40GbE QSFP+, 48 port 1/10GBASE-T with four 40GbE QSFP+ and 36 port 40GbE QSFP+ full line rate. The 1/10GbE line cards provide 640 Gbps of line rate capacity. And the 40GbE line card is based on QSFP+ form factor. From a network design perspective, the Cisco Nexus 9508 switch can be configurable with up to 1152 10 Gigabit Ethernet or 288 40 Gigabit Ethernet ports, which is very helpful for 10GbE & 40GbE migration.

Main Features of Cisco Nexus 9508 Switch

The Cisco Nexus 9508 is a versatile data center switching platform that can host 10, 40, and future 100 Gigabit Ethernet interfaces. Other than this, the switch also has other unique features:

Predictable high performance—The switch delivers 30 Tbps of non-blocking performance with latency of less than 5 microseconds, enabling data center customers to build a robust network fabric that can scale from as few as 200 10 Gigabit Ethernet server ports to more than 200,000 10 Gigabit Ethernet server ports.

Highly available, scalable, and robust solution—All major components are redundant, including supervisors, system controllers, power supplies, and fan trays. The switch line cards use a mix of merchant and Cisco application-specific integrated circuits (ASICs) to produce a low-complexity, low-cost design. All buffer memory is integrated into the forwarding ASICs, avoiding the need for a large number of external memory modules.

All transceivers are pluggable to support the highest possible mean time between failure (MTBF) for the switch. What’s more, the flexible and efficient chassis design has 100% headroom for future expansion with the capability to support more bandwidth and cooling and twice the number of power supplies needed to support today’s maximum configuration.

Power efficiency—The Cisco Nexus 9500 platform is the first switch chassis designed without a midplane. Line cards and fabric modules connect directly. This design approach provides optimal front-to-back airflow and helps the switch operate using less power. In addition, all Cisco Nexus 9000 series power supplies are 80 Plus Platinum rated. The typical power consumption per 10 Gigabit Ethernet port is less than 3.5 watts (W). The typical power consumption of each 40 Gigabit Ethernet port is less than 14W.

QSFP+ Direct Attach Copper Cabling

As we all know, direct attach cables (DACs) are often used to connect two or more switches which are in the same rack or in the adjacent rack. This is done to reduce the cabling cost for which DACs are much cheaper than transceivers and fiber patch cords. The following figure shows a wiring option for a Cisco Nexus 9396 to Cisco Nexus 93128 using 40G QSFP+ to 40G QSFP+ DAC cabling assemblies.

40G QSFP+ to 4 x 10 SFP+ Interconnection

The Cisco Nexus 9508 switch can also be operated in 4×10 Gigabit Ethernet mode. If the interface is logically configured as a 4×10 Gigabit Ethernet port, then each port becomes four 10Gbqs port. This will be accomplished by using copper twinax, hydras or breakout cables. This scenario can be achieved by connecting a Cisco Nexus 9000 Series Switch to a Cisco Nexus 2232 using a QSFP+ to four SFP+ copper hydra cable assembly.

40GE QSFP SR4/CSR4 Optics Cabling Options

Multimode fiber cabling is generally preferred when the distance between Cisco Nexus 9508 switch and other switches is less than 400 meters. In this circumstance, 40G QSFP+ SR4/CSR4 transceivers and MPO interconnect cable assemblies are often used. The following scenario shows how the Cisco Nexus 9508 switch is connected to Cisco Nexus 93128 switches with 40G QSFP+ SR4/CSR4 optics and MPO cable assemblies.

40GbE Connectivity With 40G BiDi Optics

As noted before, Cisco 40G SR-BiDi QSFP can be used in Cisco Nexus 9508 switch for 40G connectivity. The 40G BiDi QSFP multiplexes two 10GbE signals into one 20GbE stream and runs two 20GbE wavelengths on the optics side, and delivers a QSFP pluggable MSA compliant electric signal to the switch module, thereby only requiring the termination of a dual LC connector as used in 10GbE optical infrastructure. The SR-BiDi QSFP enables the re-use of existing 10GbE multimode fiber cable infrastructure plus patch cables as it supports the same LC connector. The SR-BiDi QSFP eliminates the cable infrastructure upgrade requirement of today’s 40GbE, which can lower capex of cabling and switch hardware. The following image shows the Cisco Nexus 9508 switch using 40G BiDi transceiver providing a zero-cost fiber cabling upgrade path for 10GbE to 40GbE.

Conclusion

Cisco is offering a practical way to transition to higher speed data center networking through favorable economics. With the use of Cisco Nexus 9508 switch, designers will embrace a new programmable network platform ready for the age of software-defined networking. FS.COM provides various 40G QSFP+ transceivers and fiber optic cable for the 40G connection of Cisco Nexus 9508 switch. 10G SFP+ transceivers and MPO/MTP-LC harness fiber patch cables for the 10G SFP+ to 40G QSFP+ direct connection are also provided. Please kindly contact us for more information.

People usually have the misconception about the devices like the network interface card, transceiver, modem and media converter in telecommunications fields. Some even don’t know how to use them correctly. In fact, these devices are all possessed with different functions. For example, a network interface card connects your computer to a local data network or the internet. A transceiver is responsible for taking the digital data represented by a series of zeros and ones. Modems takes the digital zeros and ones and converts it to an analog sound. While a media converter, as the name implies, is typically used to convert one media type to the other. To have a further understanding of their performances, you can have a look at the following article.

Network Interface Card

Just as said before, a network interface card (NIC) is used to connect your computer to a local data network. It functions as a middleman between your computer and the data network by translating the computer data into electrical signals. An Ethernet NIC is an indispensable transmission medium for Ethernet network. Note that we need to choose the right networking adapter that matches the transmission medium and network architecture we are connecting to. Today, most computers come with built-in Network Adapters, and the most popular one is Ethernet NIC see in Figure 1.

Optical Transceiver

On an Ethernet network, a transceiver is mainly use to convert the digital signal to an electrical, radio or light signal by a method of encoding scheme. This method uses the number zero and one to represent the voltage. A 0 might be represented as a zero voltage on the wire, while a 1 might be represented by a positive voltage. Through this method, optical technician can easily know the performance of the transceiver. The old transceiver is just an adapter that took digital signals from an AUI port on one end and translated those into an electrical signal using RJ45 or some other port. Besides this transceiver type, there are several new types that will be introduced in the below part.

SFP Module

SFP short for Small Form Factor Pluggable, is typically used on switches and routers to easily modify the media type used by a port. SFP module is one of the common type of optical transceivers that is gaining used today, especially for Gigabit Ethernet application. Other than the former devices with a fixed media type, the port accepts the SFP module. As a result, to change the media type, we can simply plug in a different SFP module. For example, we can get an SFP to support copper or a different specifications of fiber optic. Figure 2 shows a SFP modules connected by a LC LC single mode fiber patch cable in a switch.

GBIC

GBIC (GigaBit Interface Converter) module is an old transceiver module, which is slightly larger than an SFP but performs the same function. A GBIC is a larger-sized transceiver that fits in a port slot and is used for gigabit media including copper and fiber optic. Besides the GBIC and SFP (or mini-GBIC), we should also mention an XFP transceiver, which is similar in size to an SFP but is used for 10 Gigabit networking. Additionally, there are QSFP+ modules for 40 Gigabit Ethernet and CFP or QSFP28 for 100G infrastructure.

Modem

Optical transceiver is mainly used to achieve the conversion between electrical signals and digital signals by the encoding scheme. A modem takes the digital zeros and ones and converts it to an analog sound signal that can be carried across the telephone wires. Modem is actually an abbreviated term that means modulator & demodulator. Modulation is happening on the sending end where binary data is converted to analog waves, and Demodulation is happening on the receiving end where the analog waves are converted back to binary data. Note that there is an encoding scheme that identifies when the signal represents a 0 or a 1, and the Network Adapter must match both the architecture and the transmission medium that is used.

Media Converter

A media converter is usually used when you need to convert from one media type to another like from copper to fiber or vice versa. Supposing you had an Ethernet network that uses copper cabling but we had a server that had a fiber optic network adapter card. In this case we could use a fiber optic to Ethernet copper cable media converter. But one thing you should remember is that media converters work within the same network architecture. It means the media converter can convert from one type of Ethernet to another that uses a different transmission cable, but it is not used to convert from something such as Ethernet to a different networking standard.

In order to accomplish the process of converting from one architecture to another, it would require modifying the Frame contents to modify the Data Link layer address. Media converters operate at the Physical layer, since they simply transform the signal from one encoding scheme to another. However, media converters don’t read or modify the MAC address. The following image shows a SFP to RJ45 1000BASE Gigabit Fiber Media Converter.

Conclusion

At the end of the article, you might have a basic knowledge of the above devices. These devices are equipped with unique performances that play an important role in telecommunication fields. Equipment in telecom field must be correctly selected and mixed use of the is prohibited. Therefore, if you are not sure to how to use them, please seek advice from an expert. FS.COM is a rising and professional manufacturer. We not only offers a full selections of telecom products, but aim to provide the best services to the customers. If you want professional advises from us, you can directly visit http://www.fs.com.

When planning for a long-term cabling solution for your data center, it is important to consider future transmission speeds and the infrastructure to support them. Data center houses equipment like servers, storage units, backup power supplies and other equipment, which act as the heart of a building or campus. And all these equipment require high-bandwidth cables to connect them. The cabling in data center mainly comes in two forms—fiber or copper. To link the devices in data center, unshielded twisted pair (Cat5e/Cat6) and fiber optic fibers (MM fiber patch cords and single-mode fiber) are commonly used. This article will focus on cabling solution for data center, and provide the cost-effective solution to you.

Twisted Copper Solutions For The Data Center

2006 witnessed the publication of the the IEEE 802.3an standard, meaning that users can use the twisted copper cabling or 10GBASE-T to support 10 Gigabit Ethernet. Compared with the former IEEE 802.3ak or 10GBASE-CX4 standard, 10GBASE-T standard has the advantage of supporting 10 Gigabit Ethernet up to 100 meters. What’s more, the 10GBASE-T using structured wiring systems based on the RJ45 connector is less costly than the 10G optical transceivers for supporting the same Gigabit Ethernet. All this attributes to the development of the copper twisted-pair cabling for horizontal, or non-backbone, distribution between LAN switches and servers.

UTP (unshielded twisted pair) cabling is a widely adopted copper cabling solution due to its support for both voice and data applications. A UTP cable consists of insulated, copper wires twisted around each other to reduce crosstalk and electromagnetic induction between pairs. Typically a twisted pair will be enclosed in a shield (STP) that works as a ground; in other cases (UTP), the pair remains unshielded. UTP cables are often referred to as a Category cable, such as Cat5e, Cat6, or Cat7, etc.

Cat5e cables had been the standard solution and often used for legacy equipment or lower bandwidth needs. But Cat6 is the most common copper type in new installations today, especially for 10G Ethernet application. Cat5e will soon be going away, with available options being Cat6, Cat6a and Cat7. These options offer increased levels of performance and improved installations. All of these cable types can adequately provide you a connection. The differences between them lie in their transmission speed capabilities and costs.

Fiber Optic Solutions For The Data Center

In a data center, bandwidth distributed to servers and other devices may range from 1 Gbqs to 10 Gbqs or more depending on application and data center models. Fiber optic cabling are usually worshiped by overall users owing to numerous advantages. For instance, compared with copper cabling, fiber systems can provide up to 60 percent space savings over copper cabling, and it also have a greater bandwidth and error-free transmission over longer distances allowing network designers to take advantage of new data center architectures.

In practical terms, fiber cables are comprised of light, which reduces signal interruption, allowing for signals to be carried longer distances seamlessly. Though fiber cables are highly sought after, the cost to purchase and install has decreased throughout the years, making them a reasonable choice for companies seeking a reliable, scalable solution. The fiber optic cables can be mainly divided into two parts, that’s multimode and single-mode fibers.

The multimode fiber type can be separated into categories: OM1, OM2, OM3, OM4. Applied for short distances, multimode fibers have a high light-gathering capacity, meaning the use of lower cost, lower wavelength technologies like LED and vertical-cavity surface-emitting lasers (VCSELs) can be employed. For longer distances, single-mode OS1 and OS2 are used; single-mode fiber uses lasers to achieve higher speeds and further distances. Additionally, fiber optic cable terminated with different optical connectors (like SC fiber cable) are also widely utilized in data centers. Fiber optic cables are critical to network performance as they do more than join servers and connect switches. They are the foundation of your technology environment. Thus it is important to have the best options for your optical network.

Field-terminated vs. Pre-terminated Fiber Solutions

In commercial building installations, an optical fiber cabling link is typically assembled in the field at the job site. The cable is pulled in from a reel of bulk cable, cut to length, attached to the patch panel housing and terminated with field installable connectors on each end. The terminated ends are then loaded into adapters in rack or wall mountable housings. Finally, the complete link is tested for continuity and attenuation.

The most efficient optical infrastructure is one in which all components are pr-eterminated in the factory see in the above picture. Connectors are installed, tested and packaged in the factory. The installer unpacks the components, pulls the preconnectorized cable assembly into place, snaps in the connectors and installs the patch cords connecting to the end equipment. This is the fastest installation method and provides the best solution for turning up servers quickly and lessening the risk of not meeting the customer’s availability expectations. The design and product selection process remains the same with selection and specification of fiber type, fiber count, cable type, connector type and hardware type appropriate for the environment.

Conclusion

There is no absolute solution to utilizing fiber or copper cabling for data centers. Twisted pair cabling wins the broad acceptance among users owing to the horizontal medium, low initial cost, and the ability to deliver higher data rate LAN services and the flexibility to use one medium for all services. Therefore, in the majority of situations, copper cabling remains the preferred choice for the final link to the desktop, and other short links such as those found in data centers. However, with the speeds increasing and more copper cables installed, copper-based LANs will require more complex and expensive electronics. It might be inappropriate or impractical to implement in many current building environments.

While fiber optic cabling’s significant bandwidth distance gives it advantages over twisted pair in centralized architectures. Thanks to its high performance and high density, fiber optic cabling becomes an important factor where equipment density and heat dissipation are a concern. To sum up, whether to use copper or fiber for network cable type, the data center must have the best and fastest cabling. FS.COM offers a variety of integrated, holistic physical infrastructure solutions for data center intra-rack and inter rack applications. All the products including high speed interconnect optics, cable assemblies, cable management hardware etc. guarantee a reliable and stable performance for your network. If you have any requirement, please send your request to us.

The evolution of bandwidth for data transmission is unstoppable. From the 10Mbps, 100Mbps Ethernet to the 10G or 40/100G Ethernet, telecom manufacturers keep promoting higher internet speed to facilitate people’s daily life. Now, bandwidth speeds of 1Gbps to 10Gbps Ethernet capacity are commonly utilized around the world. However, with the increase in data center and cloud computing technologies, the demand for bandwidth speeds of 40G to 100G Ethernet is growing steadily for carriers and other data consumers.

Just like the dilemma of whether to use the fiber optic cable for high performance or adopt copper cable for the low cost, these high-end data consumers also have the doubt about 40G and 100G. Should we upgrade our capacity to 40Gbps or skip 40Gbpsand migrate directly to 100Gbps Ethernet? This article will help to draw an answer to this dilemma from the aspects of market trend for required bandwidth, cost and performance.

Upgrade Straight to 100G

According to today’s market trend, the tendency is to skip 40Gbps. With demanding users peeling off multiple 10Gbps channels, the 40Gbps pipe becomes quickly utilized. Carriers scaling up to 100Gbps, allows greater flexibility for one’s network infrastructure utilizing multiplexing solutions to carve multiple bandwidth channels from a single pipe. On another scale, the same is true for the consumer market where capacity is increasing from 1Gbps to 10Gbps, skipping 2.5Gbps levels, due to the flexibility and scalability 10Gbps provides at a very similar cost. In many cases, carriers and consumers have decided to skip 40Gbps and acquire 100Gbps for the following reasons and benefits:

Cost Efficiency—From a network equipment standpoint, often it may be more cost-efficient to upgrade a 10Gbps link to 100Gbps, versus 40Gbps. Essentially, if you should require 60Gbps or say even 80Gbps, additional cards would be needed to support the link in the chassis, whereas a customer may utilize only one card to achieve more than twice the bandwidth at 100Gbps. 100Gbps allows the network to operate within a smaller footprint of a data center, which in turn, reduces power consumption dissipating less heat and thus lower operational costs.

Flexibility—Creates options to provide multiple variations of delivery with handoffs ranging from 10Gbps, 40Gbps or the full 100Gbps pipes.

Scalability—Although a customer may not utilize 100Gbps on day one, the ability is there to scale the network with no forklift upgrade at any point, future-proofing the solution well beyond capacity needs.

As consumer’s demands for higher bandwidth continues to rise, many equipment suppliers, who developed some of the first 100 Gigabit Ethernet Router Interfaces, are now working on developing 200Gbps, 400Gbps up to 1 Terabyte interfaces.

This article is not implying that there is no use for 40Gbqs bandwidth level technology. Instead, I suggest that many end consumers are looking to keep up with the acceleration of high bandwidth demands while maintaining the efficiency and technologies needed to support their network infrastructure requirements while reducing operating costs.

100G Optic Solutions

FS.COM 100G transceiver solution offers customers 100 Gigabit Ethernet connectivity options for data center networking, enterprise core aggregation, and service provider transport applications. Various of 100G transceivers including CXP, CFP, CFP2, CFP4 and QSFP28 are available for different applications. The following part will lists two cost-effective 100G solutions.

QSFP28 to QSFP28 Interconnection

The QSFP28 is the exact same footprint as the 40G QSFP+, but is implemented with four 25Gbps lanes. To interconnect a multimode QSFP28 link, a 12-fiber MPO/MTP patch cable is required, while for single-mode link (100GBASE-LR4 QSFP28), a duplex LC single-mode patch cable is required. The interconnection of QSFP28 multimode link is similar with the case of QSFP28-100G-SR4 see in the following figure.

CXP/CFP to CXP/CFP Interconnection

FS.COM’s 24-fiber MPO/MTP assemblies are ideal for 100GBASE-SR10 CXP/CFP to CXP/CFP interconnection in data center, since it is implemented 10 lanes of 10 Gbps. Among the 24 fibers, only 20 fibers in the middle of the connector are used to transmit and receive at 10 Gbps and the 2 top and bottom fibers on the left and right are unused. The following picture shows the interconnection between two 100GBASE-SR10 CXP ports.

FS.COM provides a full selection of 100G optics including CFP, CFP2, CFP4, QSFP28 (QSFP28-100G-SR4) and QSFP28 DAC cables just as listed above. All of our products are fully compatible with the original brand. In addition, our 100G transceivers offer significant advantages over existing solutions in terms of reduced power dissipation and increased density with the added benefit of pluggability for reduced first installed cost. If you have any requirement, you can send your request to us.

The data center is the heart of a fiber optic network. To ensure its long-term reliable network performance, all the optical equipment within data center should be well organized. However, the current multi-fiber counts and high-density optical cabling put strain in the cable management. Fiber patch enclosure provides solid fiber-optic-link protection and space-saving cable management, which is becoming a must-have component in data center. There are several fiber optic enclosures available on the market that are widely utilized in data center or server room. This article will briefly introduce the commonly used fiber enclosure designs to better meet your data center requirement. LC to LC fiber cable and patch panels are mounted in a fiber enclosure in the following picture.

Fiber Enclosure Designs

Rack mount fiber enclosure is the commonly used type in data center as it provide a convenient and rugged termination point for fiber jumper cables. This rack mount enclosures offer a flexible connectivity system using a variety of adapter plates and MPO cassettes. The enclosures work equally as well with armored cable as they do with multiple trunk cables and are available in 1U-4U versions.

1U enclosures fit standard 19-inch racks and have rear cable management rings. 2U, 3U and 4U enclosures are designed for side or rear trunk cable entry, have removable front and rear covers, edge guards on the front for cable assembly protection and front and rear cable management rings. 2U, 3U and 4U enclosures also fit standard 19 and 23-inch racks and have a clear plastic, removable front door that can be outfitted with a label for easy identification of connections.

Except for different size, there are two types of rack mount enclosures: fiber enclosure with a removable lid and slide-out fiber enclosure (see in the following figure). The slide-out version is typically more expensive than the other version. But slide-out fiber enclosure can allow customers to remove the whole enclosure from the rack, thus, it can provide easier internal fiber connection access.

As for the design of the fiber enclosure front panel, two commonly used types are fixed front panels and removable front panel. The fixed front panel can be loaded with appropriate fiber optic adapters, while the removable front pane can accommodate several fiber optic adapter panels or cassettes just as seen in the following image.

How to Select the Fiber Enclosure

If this is your first time to install a fiber optic network, you should follow the instructions below. Only in this way can you satisfy your installation requirement, and matched your budget as well.

Physical requirement

First, list all the requirement that will be mounted in the enclosure and their complete measurements:height, depth, width, weight. All of these figures will ultimately determine what type of fiber enclosure you will need. Note that always select a bigger fiber enclosure for all your existing equipment as well as for future proof.

Critical accessories

A fiber enclosure should provide plenty of grommeted access points through the rear and top of the cabinet, as well as through the bottom for raised floor installations. Not only are the fiber optic cables mounted in the fiber enclosure, but devices like hubs, routers, patch panels, and monitors are needed to be mounted in the enclosure-network.

All servers should be protected by an uninterruptible power supply(UPS) system, available in a variety of rack-mount configurations. Thus power protection is needed. Remember that any accessories that are not rack-mountable will require additional trays, shelves and mounting accessories.

Budget

Money is always a main considerations. Thus choose the fiber enclosure that can meet your premium features at a very competitive price is the number one task. People are usually in a dilemma about whether to choose a equipment that are suitable for now or the expensive one for future proof. It is hard to say, but a premium enclosure is a durable item that will provide services for years to come.

Summary

High density fiber enclosures can maximize the amount of active equipment in a data center by minimizing the footprint of the networking infrastructure, but there’s a problem—all that fiber in a small amount of space creates problems when changes need to be made. Therefore for easiest access, quick-release side panels should be a top priority when selecting an enclosure.

With several years of experience in fiber optic cabling solutions, FS.COM offers the world-class optical products and services to maximize the performance and scalability of your data center applications. Our fiber enclosures provide the highest fiber densities and port counts in the industry contributing to maximizing rack space utilization and minimizing floor space. For more detailed information, you can directly contact us.